Containers constructed from a single sheet of corrugated cardboard and folded into a box form are well know in the art. Thousands of such boxes are used daily to provide take home containers for such foods as pizzas, after which the containers are discarded. These boxes may be formed to keep the food, such as pizzas, relatively hot for consumption. Usually vents are provided to permit steam, which would affect the taste and texture of the contained food, to escape.
Boxes for pizza are usually "assembled" as they are needed. One known form of such a box comprises a bottom, side and end walls and a top, the side and end walls being joined to the bottom by fold lines. The top is joined to an end wall at a fold line and has front and side closure flaps joined thereto by fold lines. The other and front end wall is joined to a secondary end wall at a fold line, the secondary end wall having small tabs along its free edge which register with slots at the fold line between the bottom and the end wall to thus form a double thickness front wall. The side walls are provided with tongues joined at their ends by fold lines, which tongues extend lengthwise from the side walls.
When assembling a container from a blank, the side walls are folded upwardly so as to be generally normal to the bottom, the tongues are folded to extend along the fold lines of the end members, the end wall with the connected secondary wall is folded upwardly and the secondary wall is folded into the box, over the tongues and with its tabs registering with the slots to form the double thickness front. The opposite end wall is folded at the bottom, so as to be generally normal thereto and with the other tongues inwardly of the container. The edge flaps of the top are folded and inserted into the box like assembly. Before the top is closed, the contents or product is placed onto the bottom of the container.